On The Periodic Motion And Stability Analyis Of A Flapping-Wing Mechanism With Bearing Clearance

Flapping-wing micro air vehicle (FWMA) has become a focus of research in recent years for it will be widely used in military and civilian. As one of most important components of the FWMA, the dynamic behaviors of the flapping-wing mechanism directly affect on the flight and the stability of the FWMA.At present, few studies concerning with periodic motion and stability of the flapping-wing mechanism have been reported, so much of emphasis of this thesis is placed on this issue.The main work of the study include to establish dynamic model of flapping-wing mechanism with clearance based on the two-state model, to simulate the dynamic model, and to analyze the stability of periodic motion by the Floquet-Lyapunov method.This thesis discusses what will happen to the periodic motion when the size of bearing clearance, frequency of wing beating and the friction coefficient are in variation. The result shows the changing of size of the clearance and beating frequency can directly affect the stability of periodic motion, but the affection due to the variation of friction coefficient is unapparent.As one of major factors which influence the stability of periodic motion of flapping-wing mechanism, the range of size of bearing clearance is determined.The dynamic modeling and simulations in this thesis are conducted utilizing Matlab and Visual Basic.